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Small Block to Big Block Swap Questions?>>>>

Burt4x4

1 Ton First Gen
Joined
Feb 17, 2000
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Location
California (Modesto area)
I have never done this and I am just getting started.
Does the Trany & Xfer have to be moved at all when going from SBC to BBC?
Or is it that the engine mounts in a diferent spot or is it all the same???
AHHHHHHHHHH
Any and ALL swap info you all have experianced please share with me in my quest for knowledge /forums/images/graemlins/thumb.gif /forums/images/graemlins/usaflag.gif
Late
 
Should just bolt in. Just use the big block mounts( thogh I think that it doesn't matter ) . All the brackets need to be changed for alternantor etc. Transmission stays in the same place.
 
Firewall clearance on the BBC valvecovers will be an issue. Also, the distributor (large body one at least) will be tight....

There were some factory valve covers from GM that were specially built to create better clearance at the firewall (some kind of Corvette application perhaps?)... I'd probably try for that as a solution vs. pounding the firewall out of the way, which is what the PO did to mine. /forums/images/graemlins/rolleyes.gif

I know for a fact that the 396BBC is a direct bolt-in for a 350SBC. I'm not sure if the 454 uses a different motor mount setup or not. Either way, the tranny can stay put and at the worst, you'd need to move the engine crossmember slightly to accomodate the swap.


If you want my advice, pull the front clip for the removal of the old engine and swapping in the new. It's only about 12 bolts and you take the whole fenders/hood/radiator and grill away from the work area. It makes it SO much easier it's not even funny.



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ok here i go don't know if this will help! 1967 gmc on 1971 chevy frame 454-th400-np208 i had trouble with sb firewall dist clearance. went to bb used 1974 engine crossmember offroad design engine mounts i positioned the engine so distributor clearance for hei was good i still had to clearance firewall behind valvecovers 3 pound hammer!had to use shorter fan shroud 1974 style had to drill new tranny xmember holes in anyways i have heard 1st gen sb xmembers didn't have clearance for bb's oil pan hits later style has kickout for pan you can buy bb 1st gen xmembers $$$$ plus you still have the old school motor mounts as long as you are tearing into it upgrade just my 2cents /forums/images/graemlins/eek.gif /forums/images/graemlins/eek.gif /forums/images/graemlins/eek.gif
 
Just installed my 454 into my 69, everything went smooth except for my oil pan hitting my crossmember. 454 motor mounts are exactly the same as the ones that were on my original enginge that came out of my blazer.
 
Right On guys!
Thanks
I have a 3" body lift so that should help me with FireWall clearence, I think?
Pulling the front clip...yes I was thinking about doing that...probly will. Ya it's only 12bolts but thease bolts have not turned in probly 32years /forums/images/graemlins/shocked.gif
Hmmmm I'll find out probly hehehe

I am gonna try and make a cross member that I can still remove the oil pan with out lifting up the engine.
Anyone do this..maby a new post down the road is in order /forums/images/graemlins/smile.gif
I will get the ORD mounts too /forums/images/graemlins/thumb.gif
Thanks Guys ! Keep the thought and Ideas flowing...I got till May to get this done!
Later
Burt
 
why go though all the trouble, just send me the engine and i'll put it in my blazer. when i'm done i'll show you how i did it /forums/images/graemlins/smile.gif

ARQ.
 
Hey Yukon, I like what you have done!! VERY NICE!!!
Who makes thoes valve covers? Mind if I copy you? I like um alot!!!
Thanks again for sharing!
Burt
 
Nice work, looks great! What did you use for spacers on the engine mounts and how much did you bring it up. I am putting an 87 454 in my 69 and would like to get my pan a little farther away from my crossmember.
 
[ QUOTE ]
Nice work, looks great! What did you use for spacers on the engine mounts and how much did you bring it up. I am putting an 87 454 in my 69 and would like to get my pan a little farther away from my crossmember.



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The way I understand it is that you have to move or replace the crossmember not raise the engine. I could be totaly wrong I am just learning this part as I type...hehehe
Tell us Brothers????
/forums/images/graemlins/usaflag.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/usaflag.gif /forums/images/graemlins/thumb.gif
 
I got the valve covers from Scroggin Dickey for right under $100 which seemed like a smoking deal. Here's the link - now $119 http://www.sdpc2000.com/cart.asp?action=prod_detail&catid=996&pid=810 they are part number 12495488 and you can buy the CI stickers on that page also.

I used spacers between the motor and the motor mounts to actually lift the motor a little. I used washers (hope that doesn't sound too rigged) I raised the passenger side probably 3/8" and the driver's side about half that.
 
Hmmm, Ok well lifting the engine a bit never occured to me as an option. Thanks for all your info and help...stay tuned I may have alot for questions comming up!
I need a Hydro bell housing so keep your eyes pealed for me /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/usaflag.gif
 
i had a 454 in my 78 k20 i swapped in out for a 400sbc...

I didnt change any mounts.. just bought new headers...

bolted right up.. had to cut a little off the exhaust and re weld it but no biggie...

Yes all the brackets are a little different...

You can use your distributor off the sbc into the bbc though...

/forums/images/graemlins/cool.gif
 
I'm glad your trying to go with the hydraulic clutch. That is what I'm doing also, luckily when I got my engine I got the whole truck with it, came with the hydroboost, hydraulic clutch, oil cooler, ps cooler, auxillary cooling fan, Dana 70 rear axle that went to a buddy of mine, all kinds of good stuff. The location on the block for the mechanical linkage is directly in line with one of the header tubes so I'm not sure how I could have worked around that problem if I wasn't setup with the hydraulic clutch.
 
Lucky dog!
hehe
I figure now would be the best time to do the swap.
Ya I'm thinking the heders will be an issue with the linkage as well. I guess I'll find out! hehehe
Have a good one!
Burt
 
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